New driver with shifting issues

Thank you

 

Cats make full torque at 1200rpm, that means they are going to be most efficient at 1200 or higher, you'll get the best fuel mileage at 1200 or slighly above, running lower than 1200 is lugging the engine, everyone will tell you shift at 1500, yeah that works good if you got a 13 or 18 speed, but if you have say a 9 speed, there is gonna be a 500rpm drop so its best to shift at 1700 so you drop down to 1200 and you're always in the engines efficiency range, if you ever do heavy haul and try to pull at 1000rpm you wont go anywhere, the engine wont make any boost unless you're running an acert. Lower the rpm means higher exhaust temperatures, less oil volume which means less lubrication to your bearings, valves, pushrods, ect. Notice how i said oil volume, when you tell someone running low rpm will starve the bearings of oil they say oh no my oil pressure is still at 60 or 70, my response is always yes you may have 60psi of oil pressure but you're running low rpm, the oil pump will have pressure but no flow, no volume. Its your choice to shift how you want but my experience driving and my experience as a mechanic i dont recommend ever going below 1200 loaded, the very little fuel savings do not out weigh the cons to me.rpm has very little to do with fuel savings, if you understand how the code works in an ecu you know its based on throttle position, you may be at 1700 rpm but only at 10% throttle and will burn less fuel than someone at 1300rpm and full throttle, duty cycle and pulse width makes all the difference